Grocery shopping can be a breeze or a nightmare, depending on what time you go to the store. If you're like me, you probably loathe waiting in lengthy checkout lines for a bag of greens and a gallon of milk. I'm a bit ashamed to admit this, but I will find random things to buy if I wait in the checkout line for more than a few minutes — namely the candy bars, sugary honey-roasted peanuts, and beef jerky which conveniently line the aisle.

I don't know what it is about waiting in line that makes me grab unhealthy food items I don't need — or even want, for that matter — but I have learned that grocery shopping can set you up for a week of strategic success, or a week where you throw all nutrition and meal planning out the window.

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If you're trying to lose weight, here's when you should go grocery shopping.

After You've Made a List

Be like Santa — make a list, and check it twice. Cooking Light has a great section called "Cook Once, Eat 3 Times" where you can buy a couple of staple ingredients and use them in multiple ways. It's great for people who have meal prep fatigue or are trying to pare down their grocery list to just the healthy basics. No matter what you do, just make sure you have a grocery list of all the items you'll need for the week — a guided outline will help you stay on track and stick to your diet plan.

When You're Full

If it's 3 p.m. on a Sunday and you skipped lunch, do not head to the grocery store! We've all experienced the exorbitant grocery bill after a hunger-fueled shopping trip — and, take it from my personal experience, nothing good ever comes from shopping with an appetite. Hunger primes your brain to crave junk food, and you'll end up walking out of the store with eight bags of chips, a pack of steak, and a handful of candy from the checkout line (or, so I've heard).

In the Morning

Grocery stores are most crowded on weeknights between 4 p.m. and 6 p.m. (read: the after-work dinner rush). Grocery stores are also packed on weekends, so try and do your shopping in the mornings if possible. Another strategy? Go after dinner during the week, around 8 p.m.

It's worth mentioning that meat, produce, and bread are all freshest first thing in the morning, but you should always get the scoop from the store's department managers. For example, if you love shrimp, ask the seafood department when fresh shipments arrive or when pricier items will be marked down. If you're trying to get the freshest ingredients, it may be worth setting your alarm an hour earlier.